Interfaces of various schemes have been proposed as input interfaces for acquiring an input from users to control operations of so-called information processing devices such as personal computers (PCs) and game machines. Particularly in recent years, as so-called voice recognition technology and natural language processing technology has developed, user interfaces (UIs) that enable users to input various kinds of information through a voice have become widespread. Patent Literature 1, for example, discloses an example of a mechanism using a so-called voice recognition technology.
A voice input by a user can be converted into, for example, so-called character information and presented by applying the above-described voice recognition technology and natural language processing technology thereto. In addition, the character information resulting from the conversion of the voice can also be applied as an input to various kinds of control, for example, when the semantic content of the character information is recognized.